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R34 Rb25De To Rb25Det Conversion Auto Gearbox Problems?

Myfine Skyline R34!
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Myfine Skyline R34! Enthusiast

Myfine Skyline R34!

Posted
Posted

Any help or advice on this would be really appreciated guys.

I have a 4dr R34 with the tiptronic transmission, It had an RB25DE in it and I wanted to carry out an engine conversion to the RB25DET.

So I bought the engine from just jap, and the ecu and wiring loom for a GTT auto. Autosport did the conversion for me but then told me that

it was in limp mode, and the transmission was staying in top gear only. he said that it was because the ecu was for a turbo gearbox and also thought

that the transmission module had been short circuited during the wiring process, So I bought another transmission module from Sydney auto dismantlers

and had it fitted. Didn't change a thing... So now after spending a few more days on it he has told me that the tip-tronic mode works, but it has very lumpy gear changes in drive,

and the oil temp, tps sensor doesn't work therefore the gearbox operating at 90%.

He also said the only way to rectify this problem is to either buy a turbo tiptronic box, or convert the car to manual.

Does anyone know about this sort of problem I have and if there is another solution to make my current box operate properly.

I have been without my car now for 5 weeks and am quite disheartened to hear this is the result of the conversion...

Thanks for taking your time to read this and I hope one of you have encountered or have known about this problem and know how to rectify it another way.

  • 2 weeks later...
N-DAWG Mentor

N-DAWG

Posted
Posted

I've just done this swap on mine using GTT auto ecu and runs fine?

I've had a shift kit and rebuild so can't comment on thump changes?

I used TPS from the n/a motor with a gasket and silicone pipe to extend it.

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